Anionic surfactants, particularly, alkyl sulfates and alkyl polyoxyalkylene sulfates, are excellent in detergency and foaming power, and thus are widely used as cleansing ingredients for domestic or industrial use. An olefin sulfonate, particularly, an internal olefin sulfonate obtained with an internal olefin having a double bond inside an olefin chain, not at its end, as a raw material, has been reported as one of the anionic surfactants.
Such an internal olefin sulfonate is generally obtained by sulfonating an internal olefin through reactions with a gaseous sulfur trioxide-containing gas, followed by neutralization and then hydrolysis of the resulting sulfonic acid. The internal olefin sulfonate is known to have good biodegradability or the like, but is still insufficient in a basic performance as cleansing agents including foamability and foam quality, compared with general-purpose surfactants such as salts of alkyl polyoxyalkylene sulfuric acid esters. Thus, further improvement in such basic performance has been desired. As more people have concerned the water-saving in recent years, the additional value of foam dissipation property in addition to good foamability, foam quality, foaming speed, and foam durability in the presence of model sebum has also been required for use as active ingredients in laundry detergents, dishwashing detergents, shampoos or the like.
Patent Document 1 discloses a specific internal olefin sulfonic acid for the purposes of the solubilizing ability, penetrating ability, and interfacial tension reducing ability. It discloses that when it is used as a shampoo, it lathers well without friction, and achieves an improved feel.
Patent Document 2 describes a specific internal olefin sulfonate for the purposes of improving detergency, and discloses examples of application to shampoos and the like, and Patent Document 3 also describes an aqueous liquid cleansing agent containing a specific internal olefin sulfonate and having a low cloud point.